Sign, stamp and compress PDFs on your Mac. Free.
1Scanner does the PDF jobs Preview makes hard: your signature and company seal on any page or all of them, a file shrunk to the size a website asks for, a document split by page ranges. Merge, reorder and protect PDFs, and read QR codes from pictures and PDFs. Your files never leave your Mac.
How to install 1Scanner on your Mac
- Open the downloaded
1Scanner-1.1.0-3.dmg. - Drag 1Scanner to the Applications folder.
- Open 1Scanner from Applications. It is signed with a Developer ID and notarized by Apple, so macOS opens it like any other app.
Add your signature and company seal to a PDF on Mac
Sign or stamp a white sheet of paper, take a photo with your iPhone or scan it, and 1Scanner removes the paper. The ink keeps its own color, so a red seal stays red.
- Keep your signature, initials and company seals ready for every document.
- Put one on a page, then move, resize and turn it. Add it to every page at once for initials or a seal on each sheet.
- Ready stamps like PAID, APPROVED and COPY, with today's date if you like, or a signature drawn with the trackpad.
- The page's own text stays text in the signed copy.
Your PDFs stay on your Mac with 1Scanner
Contracts, IDs and invoices are exactly what you should not upload to a website to compress or sign. 1Scanner does everything on your Mac and has no account, no ads and no analytics or tracking SDKs.
No upload
Opening, signing, compressing, splitting and reading codes all happen on your Mac. Nothing is sent anywhere.
Originals untouched
1Scanner only reads the files you open. Every result is a new file, saved where you choose.
Online only when you ask
The app goes online only when you check for updates or install one: it reads one small file on onebuckapps.com and, for an update, downloads the new version from there. Read the full privacy policy.
Compress a PDF on Mac to the size you need
Job portals, visa forms and email often accept only files up to 1 or 2 MB. Choose Medium, Small or a limit from 0.2 to 20 MB, and see the real size of each file before you save it.
- Pictures inside the PDF get smaller; text and lines stay sharp and selectable.
- When a strict limit can't be met that way, the pages become pictures so the file fits, and 1Scanner tells you that text in that copy can't be selected.
- Signatures and seals are saved at the size they appear on the page, so they add little.
Split, merge and rearrange PDF pages on Mac
Split a PDF by page ranges like 1-3, 5, 8-10, every few pages or page by page, in one step. Merge PDFs and images in the order you set.
- Reorder pages by dragging, rotate them, delete them, insert pages from other files and extract the ones you need.
- Turn photos and scans into one PDF, or export pages as PNG or JPEG pictures.
- Save a copy protected with a password, or a copy of a protected PDF without its password.
Read a QR code from an image or PDF on Mac
Drop a picture or PDF, or paste a screenshot. 1Scanner reads every QR code and barcode on every page and shows what each one holds.
- Nothing opens by itself. A link shows its full address with the real site highlighted first.
- Warnings for look-alike sites, unencrypted links, bare IP addresses and short links.
- Wi-Fi codes show the network name and password, ready to copy.
1Scanner and Preview on your Mac
Preview comes with every Mac and is good for reading, highlighting, filling forms and a quick signature. Keep using it for that. 1Scanner is for the jobs Preview leaves to you.
Compress to a size
Preview's Reduce File Size has no size target and no preview of the result. 1Scanner shows the real size of each choice and fits a limit you set.
Seals and stamps
Preview signs with a drawn or photographed signature. 1Scanner also keeps company seals and stamps with the paper removed, and adds one to every page at once.
Split by ranges
Preview has no split command: you drag selected pages out or print a page range to PDF, one file at a time. 1Scanner makes a file per range, like 1-3, 5, 8-10, in one step.
1Scanner for Mac is free, with optional support
No subscription, no paywall, no ads. If 1Scanner saves you time, you can support the developer with a crypto donation.
Questions about PDFs on a Mac with 1Scanner
How do I compress a PDF on a Mac to a specific size?
Open the PDF in 1Scanner and set a size limit, for example 1 MB. 1Scanner makes the file on your Mac, measures it and shows its real size before you save. It first shrinks only the pictures inside the PDF, so text stays sharp and selectable. If that is not enough, it turns the pages into pictures, and says that text in that copy can no longer be selected. Not on your Mac right now? 1Scanner Web compresses to a size limit in a current browser, without uploading the file.
How do I add a company stamp or seal to a PDF on a Mac?
Stamp a white sheet of paper, take a photo of it with your iPhone or scan it, and add the picture to 1Scanner. The paper becomes transparent and the ink keeps its own color. Then put the seal on the page, resize and turn it, or add it to every page at once.
Can't I just use Preview?
Preview is free and good for reading, highlighting and a quick signature. It has no size target when it reduces a file, no library of seals and stamps with the paper removed, no way to add a stamp to every page at once and no split by page ranges. 1Scanner does those jobs and is free too. Both ways step by step: how to sign a PDF on a Mac.
Are my PDFs uploaded anywhere?
No. Everything happens on your Mac. The app goes online only when you check for updates or install one: it reads one small file on onebuckapps.com and, for an update, downloads the new version from there. Details are in the privacy policy.
Is 1Scanner for Mac really free?
Yes. There is no subscription, no paywall and no ads, and every tool works. If the app helps you, you can support the developer with an optional crypto donation.
Does a signature added with 1Scanner make a document legally binding?
1Scanner puts your own signature and stamp images on the page, like signing a printout. Whether that is enough for a given document depends on who asks for it; some need a certified digital signature, which 1Scanner does not create.
How do I scan a QR code from a screenshot on a Mac?
Copy a screenshot of the code (Command-Control-Shift-4 copies a selected area) and paste it into 1Scanner, or drop a picture or PDF on it. 1Scanner reads every code on every page and shows what each holds. A link shows its real site and any warning before you open it.
How do I uninstall 1Scanner?
Quit 1Scanner and drag it from Applications to the Trash. Its signatures and stamps live in ~/Library/Application Support/1Scanner and its settings in ~/Library/Preferences/app.antosha.onescanner.mac.plist; delete them too if you want nothing left behind. Version 1.0.0 also left ~/Library/Containers/app.antosha.onescanner.mac.
Is 1Scanner for Mac open source?
Yes. The source code is on GitHub under the GPL-3.0 license. You can read how it handles your documents, build it yourself or report a problem.
Sign it, stamp it, make it fit.
Free PDF tools that work on your Mac, not on someone's server.
Version 1.1.0 · macOS 14 or later · Apple Silicon & Intel · 17 languages · free · open source